Storefront framing systems are well known and widely used. A framework of vertical frame members, known as mullions, and horizontal frame members is installed within an opening in the exterior wall of the building. Glazing panels are set within the openings defined by the vertical and horizontal frame members.
A common problem associated with such structures is that water running down the face of the adjacent condition tends to penetrate and drip into the open upper end of the vertical frame members and thus enter the building. This problem is particularly acute in the case of storefront and curtainwall framing systems installed in buildings constructed of masonry walls, for example, walls of pre-cast concrete. For aesthetic reasons vertical frame members of the storefront or curtainwall framing systems are frequently positioned to coincide with seams in the masonry walls. For example, a vertical frame member might be positioned beneath a seam between adjacent concrete panels. Water dripping down the face of the concrete wall tends to run along the seam and thus be directed into the open upper end of the vertical frame member.
The common solution for this problem is to install flashing over the open upper end of the vertical frame members. However, this solution is costly because it is labor intensive. Further, if the flashing is not properly installed, such as by a careless or unskilled worker, water can leak around the flashing and into the open upper end of the frame member.
Thus there is a need for a system which prevents water from entering the open upper end of a vertical frame member in a storefront framing system where the arrangement is not labor intensive and can be easily and effectively installed by unskilled labor.